Respirators, particularly for submarine use



INVENTORS PM/wz, 14mins rs.

United States Patent RESPIRATORS, PARTICULARLY FOR SUBMARINE USE Claes Erik Gunnar-Lundgren and Mans Mfinsson Arborelins, both of Hamngatan 1A, Stockholm, Sweden Filed Dec. 26, 1956, Ser. No. 630,533

Claims priority, application Sweden Dec. 30,1955 1 7 Claims. or. 128-142) I In respirators for submarine'use certaindifiiculties are valves against a pressure, which is approximately equal 2,944,544 Patented July 12, 1960 to or lesser than the water .pressureresting on the thorax of the diver. One of the exhaust valves may be that one p which isgene'r'allyarrangedin the gaiscontrotniechamet with on account'of thedeleterious varying breathing resistance created in difierent under water positions depending on the fact that 'the various parts of 't-he'appa: ratus and the thorax of the diver are atrdifierent depths and consequently subjected to different hydrostatic pressures varying relatively to one'another.

In respirators for submarine use with a so-calledop en system, the apparatus consists of a control mechanism connecte dto a compressed gas container and of' anexhaust valve. In breathing the control mechanism admits the'requisite quantity of gas into an inhalation channel,

the pressure of which gas is reduced at thes ame time. For the purpose in view a diaphragm valve actuated by the water pressure, generally a so-called demand valve, is made use of. 1

It is desirable that the demand valve and theexhaust valve be located in the apparatus in a manner such as to V be near the lungs. of the diver inthe service position of the apparatus, in order to bepermitted to operate as far as possible under the same pressure conditionsas the divers lungs. In known constructions, the demand and exhaust valves are arranged in different places, by

reason of which incertain under water positions a pressure is created on the diaphragm of the demand valve which is greater than the pressure actingon the exhaust valve, gas being then permitted to escape continuously from the demand valve with gas losses in consequence thereto, inasmuch as the gas Will then flow from the de- "mand valve to the exhaust valve directly. Endeavours v have been made in earlier constructions to avoid this ;-of the gas control mechanism.

drawback making theexhaust valve so as to open only at a certain overpressure, which is adapted by means of springs or the like so as to precisely exceed .the maximum pressure difierence that may set in between the demand valve and the exhaust valve. This, however, in-

volves the disadvantage of an increased expiration resistance. V p v The object of the present invention is in respirators of the type in question toarrange the control mechanism :and the exhaust valve so that the drawbacks touched upon will be obviated. To this end the'exhaust valveis loaded, according to the invention,.with-a closing pressure, which 1 is the same as the pressure prevailing in the gas chamber Since the gas control ,-mechanism consists ofyan inlet valveforthe'compressed gas arranged in adiaphragm box, this may. be'attained -haust valve into the diaphragm box.

in the simplest possible manner by incorporating the ex- According to another embodiment of the invention, however, theexhaust valve may instead be arranged in a chamber which is in open communication with the gas chamber of the .gas control mechanism.

:irrespective of the position of the diver in the Water- :zpiration air is admitted to escape against the'same pres-.1

The invention refers also to an. application, in which,

for instance a back posit-ionor'abreast' position'-the exmitterd to :enter, inasmuch as this-is prevented 'byv the nism through which the" respiration 'gas enters from the container of'compr'essed gasfwhereas'theother is cohstituted by. an additional exhaust valve arranged on the opposite side of the body. The expiration air escapes always through that one of these valves in which the resistance is the least, thatis'to say, generally the valve taking the highest positionin the water, where the water pressure is consequently the least. The additional exhaust'v'alve-is constructed so as to open only at an overpressure relatively to the ambient water which is adapted 'to'the greatest pressure difference that may set in between any'part of'the remainder of the gas system and the addional exhaust*valve,-- Y

A few examples of applying the invention will be df I scribed in the following with reference to the accompanying drawing, in which the invention is illustrated througha few diagrammatic figures. Fig; 1 shows a first embodiment in an axial section through a diaphragm box, and'Fig. 2 shows a plan sectional view through the diaphragm'box in this embodiment. Another embodi- 'ment is shown in Figs. 3 and 4 in two sections at right angles to each other. Fig. 5 illustrates the diver; in his breast position and with thespecial embodiment of the invention, and Figl'6 shows his "back position, the main parts of the apparatus being indicated in a central sectionalview. i4

In the embodiment according to Figs. l'and 2, the control mechanism is taken to comprise a conventional demand valve.' The diaphragm box is designated by '1 and the diaphragm thereof by'2. Reference numeral 3 denotes the valve body connected to thediaphragm 2 and cooperating with the seat '4 in the valve housing 5 of the inlet valve, in which compressed-gas is supplied tothe diaphragm box through a supply conduit 6 con- .nected to a container of compressed gas. An inhalation tube 7 with a non-return valve 7' and an expiration tube 8 are connected to a respiration nozzle 9. The inhalation tube 7 is connected to an opening 10 in the wall of the diaphragm box, and the expiration tube 8 is connected to a pipe socket 11 in the same wall. The exhaust valve in this case built into the diaphragm box. It consists of a soft-walled flattened tube 12 for instance from rubber, oneend ofwhich is slipped over the pipe .socket 11, while its other'en-d is connected to a pipe socket- 13, which is preferably, arranged diametrically opposite the pipe socketll in thewall ofthediaphragm' box. fTheI pipe socket 13 projects outwardly on'the out side of the diaphragm box, and they projecting parthas arranged thereon a non-returnvalve 1 t, which in the construction shownv is taken'to' consist ofa so-called duck nib valve ;from ru bber' or other suitable material. 'Thefmode of operation of'the embodiment described is broadly as follows. 'When inhalation takes place through the tube 7 and the'noz'zle 9, the compressed air valve 3 is opened by. the diaphragm 2 then bulging somewhat-inwardly. On the other hand, "nofwater :isjp'ernon-return valve 14, which is kept closed bythe water pressure. When expiration takes place through the nozzle 9 and the tube 8, the valve 3 is first automatically closed by reason of the resiliency of the diaphragm 2, and then non-return valve 7' prevents the expiration air from flowing through the tube. In the expiration tube, and thus also in the lungs, the pressure need only exceed the gas pressure of the box 1 acting on the walls of the valve 12 and the water pressure resting on the valve 14 to cause the expiration air to escape through the valve 14. This does not involve any dithculties in the construction shown, when the lungs are at a greater depth than the valve. These operating conditions prevail in the control mechanism even if the pressure in the diaphragm box is altered relatively to the pressure of the ambient water through loading with a weight or spring.

The exhaust valve may be built into a bladder or sack instead of'being arranged in a diaphragm box. A particula'rly suitable construction may be obtained, if the bladder or sack is'formed as a bellows in the manner shown in Figs. 3 and 4.

As shown in Figs. 3 and 4, a bladder or sack is formed with three bellows-shaped sides 23, while it is secured on the other sides on a pair of flaps, one of which 24, 2.5 is formed by an angularly bent plate covering the bottom .(24) and the one side wall 25 of the sack, while the other flap 26 is connected to theupper edge of the lastmentioned side wall by means of a pivot 27 so as to be permitted to move toward and from the flap 24. Provided on the flap 26 is an inlet valve 28 for compressed gas or air supplied through a pipe 29. The exhaust valve has the shape of a duck nib valve 30 having its inlet end connected to a socket 31 in the wall 25 and its opposite flattened outlet end 31' projecting through the bellows Wall 23. The duck nib valve is preferably made from soft rubber and is, for instance by vulcanization, secured tightly in a projecting fold 32 of the bellows wall 23. The bellows folds are large enough to cause the expiration air need only just exceed the outside pressure in the sack 23 to cause the valve 30 to open. For example, it at inhalation lower pressures are created in the sack 23 and thus in the valve 30 than in the water surrounding the sack, the water is prevented from penetrating into the valve 30, because the flattened end 31' of the valve 30 and the fold 32 act as a non-return valve.

To permit the expiration air to escape from the valve 30, the pressure in the ambient water must be overcome.

In the construction shown in Figures 5 and 6, the apparatus consists of a bellow-shaped bladder or sack 1 with stiff walls on three sides, the same forming two flaps 2, 3, which are pivotally connected to each other by means of a hinge 4. Compressed gas is supplied to the bladder through a tube 5 and an inlet valve 6, which dispenses gas in suitable proportions. An'expi'ration tube 7 from a nozzle 8 opens into the bladder through a socket 9, to which is connected an exhaust valve 10 built into the bladder, said valve taking the form of a so-called duck nib valve. This valve, which in principle consists of a tubular piece of rubber or other elastic material flattened toward its outlet end, opens with this outlet end outside the bellows wall 11 of the bladder through a fold in said wall. Arranged on the stiff wall 2 of the bladder is a weight 15, which by its action on the flap'Z increases or decreases the pressure in the bladder by a force that compensates for the difference in the static pressure of the water on the bladder in the breast position (Fig. 5) on one side and in the back position (Fig. 6) on the other side.

Connected to the expiration tube 7 or optionally to the bladder 1 directly, through a tube 13 is a second exhaust valve 12. This valve may consist of a spring actuated diaphragm valve. Thetubes 7 and 13 are in open communication with one another. The expiration air may consequently escape either through the exhaust valve 10 or through the exhaust valve 12 and then chooses the path oifering the least resistance. Extending between the nozzle 8 and the bellows 1 is an inhalation tube 16 with a non-return valve 17;

In Figures 5 and 6 of the drawing, the average level of the divers lungs in breast position as well as in back position is indicated by a chain-dotted line 14. The thickness of the divers thorax is denoted by 2a cm. and the static pressure of the water on the bellows 1 in breast position (Fig. 5) by A.

In breast position of the diver, the bellows 1 is acted upon by a pressure of A cm. water column. The pressure in the divers lungs is higher, however, depending on the pressure-compensating weight 15. Thus it amounts to (A plus 2) water column. The same pressure (A-I-a) acts on the exhaust valve 10 located in the bellows. The exhaust valve 12, which is at a 2a cm. greater depth than the bellows 1, is acted upon by a water pres sure of (A plus 2a). Against the expiration is here added the pressure T on the spring of the exhaust valve 12; in other words, the diaphragm of the valve is acted upon by a pressure of (A plus 2a plus T) cm. water column.

The expiration air escapes through that one of the exhaust valves 10, 12 which is acted upon by the lowest pressure, that is to say, through the valve 10, where the pressure was (A plus a). The same average pressure prevails in the divers lungs, which thus only have to overcome an immaterial resistance for expiration.

In the back position of the diver (Fig. 6'), a pressure of (A plus 2a) cm. water column prevails on the bellows 1, and the same water pressure acts at the outlet opening of the valve 10. The pressure is less within the bellows, because the weight 15 now acts in the opposite direction, that is to say with a reducing elfect on the pressure. The pressure in the bellows constitutes (A plus 211 minus a)=(A plus a) cm. The pressure (A plus a) also prevails in the lungs, and the valve 12 is acted upon by the pressure A plus T. The pressure of the expiration air must not exceed the pressure in the lungs, that is to say A plus a, for which reason the spring pressure T shall be equal to or somewhat higher than a cm. water column. The pressure in the bellows 1 must not exceed A plus T, for in that case gas would flow continuously out of the apparatus.

In back position, the expiration air also escapes through the uppermost exhaust valve, that is to say the valve 12 in this case, where the pressure is lower than in the lowermost valve. Obviously, the spring pressure T may be adapted so that the expiration resistance in back position becomes equal to or approximately equal to the resistance in breast position.

-It has been assumed in the foregoing that the average level 14 of the lungs is midway between the valves 10 and 12, that is to say at the same distance from both of these valves. If the distance to one of the valves is greater, the spring pressure T should be adapted in consideration of this fact, so that it becomes equal or approximately equal to the difference in water pressure at the level of the lungs and the level of that one of the exhaust valves which is at the greatest distance from the average level in the back position or breast position of the diver.

The invention is not limited to the construction shown, which only relates to an example. .For example, the bellows contrivance may be replaced by a diaphragm valve, for instance by a so-called demand valve, into 7 the diaphragm box of which an exhaust valve of the same f typeas that designated by 10.01 a similar valvemay'be incorporated- Certain cmbodimentsof the invent on can bemodified for use also in smoke diving apparatus.

What we claim is: I

1. 'In" respirators an arrangement comprising a dia- I phragni box forming a. gas chamber, an inlet"valve for admitting compressed inhalation-gas 'intorsaid chamber in dependence upon. the pressure in said. chamber, an

a e r344 to or lower than the water pressure resting on the'thorax of the diver.

5. Ar -apparatus for. respirators for submarine use comd prising an expiration conduitfa bellows communicating .withf'theexpiration conduit, an inlet-lvalve for inhalationf f gas opening into said bellows, an exhaust conduit for expiration gas, two exhaust valves communicating with said expiratory conduit with iiexible glwallsfpassing through) v the chamber, said conduit forming an exhaust valve exposed to the gas pressure prevailingin the gas chamben 2. A gas control apparatusfor respirators for submarine use, comprising a diaphragm box including a gas.

chamber, an inlet valve for compressed inhalation gas controlled by the diaphragm ofsaid'diaphragm box, an

exhaust valve for expiratory gas comprising a flattened hose passing through said diaphragm box so as to be exposed to the gaspressure prevailing therein, a non-. return valve mounted outside the diaphragm boxon the outlet end of said hose, an inhalation tube'communicating to the inlet end of said hose. V 3 .-Arr apparatus for" respirators for submarine use,

with said gas chamber and an expiration tubeconnected exhaust conduiu means 'forimounting' one of said exhaust valves on the breast sidefland the other exhaust valve on the back side'of the diver, one exhaust, valve being thorax of the diver.

6. An apparatus as claimed in claim 5, in which the bellowscomprises means tocompensate for the difference-in water pressure at the level of the exhaust valve mounted therein and that prevailing at the level of the divers lungs;

7. An apparatus for respirators for submarine use comprising an expiration conduit, a bellows communicating comprising a bellows having at least two'stifi' walls, said bellowsforming a'gas chamber, an inlet valve for compressed aspiration gas opening into said gas chamber,"

and an exhaust valve formed by a flexible conduit having an inlet end and an'outlet end and extending through. 3

one stifi wall and passing said gas chamber and-through a bellows fold at its outlet end, said outlet end forming a non-return valve adapted to open into the ambient water, but preventing water to flow into said conduit.

v 4. An apparatus for respirators for submarine use comwiththe expiration conduit, an inlet valve for inhalation gas opening into said bellows, an exhaust conduit for expiration gas, two exhaust valves communicating with said exhaust conduit, means for mounting one of said exhaust valves onthe breast side and the other exhaust valve on the. back side of the diver,', one exhaust valve being mounted in said bellows, means to compensate for the difference in 'waterpre'ssure at the, level-of the exhaust valve mounted inthe bellows and that prevailing at the level of the diveris lungs, the other exhaust valve being -.loaded with a spring ,force equal to or immate'rially prising an inlet valve for inhalation gas, an exhaust conduit for expiration gas and two exhaust valves communieating with said exhaust conduit, means for mounting one of said exhaust valves on the divers breast side, the other of said exhaust valves being adapted to be mounted'on the divers back side and means to .load said exhaust valves with closing pressures permitting expiration gas to escape through said valves against pressures, approximately equal greater than the difference in water pressure at the level of the divers lungs and the level of said otherexhaust valve.

' References Cited in the file of this patent .UNITED STATES PATENTS 2,764,151 Cupp Sept. 25, 1956 I 

